1. Field of the Invention
The invention relates to a system for antenna extension and a method thereof, and in particular relates to a system, which carries out antenna extension by combining a handheld device with a base device, and a method thereof.
2. Description of Related Art
Wireless communication system is developing and advancing rapidly. In the process of development, the technology of Multiple Input Multiple Output (MIMO) is gradually applied to the new communication system. According to the 3rd Generation Partnership Project (3GPP) standard, MIMO has been included as a system requirement in Evolved High Speed Packet Access (HSPA+) and Long Term Evolution (LTE) standards. According to Long Term Evolution-Advanced (LTE-Advanced) standard which is about to be established completely, not only the receiving terminal needs to incorporate MIMO technology, the transmission of the user equipment (UE) also needs to provide multiple-output function. In addition, the LTE-Advanced standard may very likely evolve to support 4T8R. As a result, the antenna space configuration for user equipment and the fabrication thereof will become more difficult.
The currently-adopted solution for MIMO is to configure all the antennae in the handheld device, but there are some limitations and disadvantages. First, due to the limited space, the radiation efficiency of the antennae would be worse. In addition, antennae configured into limited space may influence each other and quite often cannot meet the system requirements, resulting in low system transmission efficiency. According to LTE standard which is the mainstream, a mobile phone system can support multiple antennae of 1T2R (one transmitting antenna and two receiving antennae) or 1T4R (one transmitting antenna and four receiving antennae) at maximum. However, the design of two receiving antennae is difficult to realize in a handheld device due to the limited space. And, it will be even more challenging to configure four receiving antennae. Therefore, how to dispose multiple antennae into the limited space of the current handheld devices has become an important issue.